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11.
Pheochromocytomas of the bladder are rare neoplasms, constituting <0.06% of all vesical tumours. Common presenting features of this tumour include episodes of sweating, hypertension, haematuria and postmicturition syncope. We describe a case of bladder pheochromocytoma in a 66‐year‐old man whose only symptom of macroscopic haematuria was initially assessed with ultrasonography. Clinical presentation highlights the need for a high index of suspicion during sonographic evaluation of bladder neoplasms because such tumours might present without symptoms of adrenergic excess.  相似文献   
12.
Upham  BL; Kang  KS; Cho  HY; Trosko  JE 《Carcinogenesis》1997,18(1):37-42
Cell to cell communication via gap junctions is essential in the maintenance of the homeostatic balance of multicellular organisms. Aberrant intercellular gap junctional communication (GJIC) has been implicated in tumor promotion, neuropathy and teratogenesis. Oxidative stress has also been implicated in similar pathologies such as cancer. We report a potential link between oxidative stress and GJIC. Hydrogen peroxide, a known tumor promoter, inhibited GJIC in WB-F344 rat liver epithelial cells with an I50 value of 200 microM. Inhibition of GJIC by H2O2 was reversible as indicated by the complete recovery of GJIC with the removal of H2O2 via a change of fresh media. Free radical scavengers, such as t-butyl alcohol, propylgallate, and Trolox, did not prevent the inhibition of GJIC by H2O2, which indicated that the effects of H2O2 on GJIC was probably not a consequence of aqueous free radical damage. The depletion of intracellular GSH reversed the inhibitory effect of H2O2 on GJIC. The treatment of glutathione- sufficient cells with H2O2 resulted in the hyperphosphorylation of connexin43, which is the basic subunit of the hexameric gap junction protein, as determined by Western blot analysis. TPA, a well-known tumor promoter, also inhibits GJIC via hyperphosphorylation of GJIC, which is a result of protein kinase-C activation. However, H2O2 also induced hyperphosphorylation in GSH-deficient cells that had normal rates of GJIC. Therefore, the mechanism of GJIC inhibition must be different from the TPA-pathway and involves GSH.   相似文献   
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BACKGROUND: Quality of life (QOL) assessment has emerged to measure and quantify the balance between treatment benefit and toxicity, and has a value in predicting response and overall survival in cancer patients. METHODS: From July 1995 to February 1997, 38 symptomatic patients with advanced non-small cell lung cancer (NSCLC) were treated with MIP chemotherapy (mitomycin 6 mg/m2, ifosfamide 3000 mg/m2 and cisplatin 50 mg/m2 on day 1 every 3 weeks). Patients were assessed for QOL including physical well-being, general symptoms and lung cancer-specific symptoms, as well as objective response. RESULTS: The overall response rate was 38.9% (14/36, all were partial response) and the median duration of response was 3.5 months [95% confidence interval (CI) 2.0-4.0]. The median duration of overall survival was 7 months (95% CI 5.9-8.5). The overall improvement of QOL was 58.3% with 21 patients feeling better on treatment. The toxicity of chemotherapy was mild, mainly nausea/vomiting and minimal alopecia. Using multiple clinical predictors of survival (age, histology, stage, performance status), only change of QOL emerged significantly (P = 0.0007). CONCLUSIONS: MIP had an endurable response and low toxicity profile, and provided good QOL. Integral QOL data in our study provided the strong prediction of survival in advanced NSCLC. Further experienced QOL study will provide greatly enhanced outcome data in clinical trials.   相似文献   
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Current knowledge about molecular mechanisms underlying disease progression and drug resistance in multiple myeloma (MM) is still limited. Here, we analyzed the potential pathogenetic role of the Y-box binding protein YB-1 in MM. YB-1 is a member of the cold-shock domain protein superfamily and involved in various cellular functions such as proliferation. Immunohistochemical analyses revealed that neither normal bone marrow (BM) plasma cells (PCs), premalignant PCs of patients with monoclonal gammopathy of unknown significance (MGUS), nor MM cells with a mature morphology showed expression of YB-1 in situ. In contrast, YB-1 was strongly expressed in situ in normal PC precursor blasts as well as in a MM subset and in vitro in all of the evaluated MM cell lines. The YB-1-expressing MM cells were characterized by an immature morphology and a highly proliferative phenotype as defined by Ki 67 expression. We observed that siRNA-mediated knockdown of YB-1 decreased proliferation and induced apoptosis in MM cells even in the presence of BM stromal cells. Furthermore, we found that overexpression of YB-1 mediated resistance toward doxorubicin-induced apoptosis in MM cells. Thus, YB-1 contributes to disease progression, survival, and drug resistance in MM and might therefore provide an attractive therapeutic target.  相似文献   
16.
Incorporating photocatalytic nanoparticles with biochar templates can produce biochar-supported photocatalysts (BSPs) and combine the advantages of biochar with catalytic nanoparticles. The obtained composite exhibits excellent surface properties, crystallinity, chemical stability, recoverability, and higher photocatalytic competency than the bare semiconductor photocatalyst. The literature and advances in BSPs based on the combination of low-cost biochar and catalytic nanoparticles are presented in this review. Various synthetic techniques and physicochemical properties of BSPs are summarized. The article then discusses in detail the important role of biochar in influencing the photocatalytic performance of BSPs such as supporting nanoparticles, increasing the surface area and the number of active sites, shuttling electrons, acting as an electron reservoir, increasing charge separation, and reducing band gap energy. Furthermore, the synergistic effects of adsorption and photodegradation of organic pollutants by BSPs are discussed with in-depth mechanistic evidence. Finally, the application of BSPs in various fields and constructive suggestions for their future development are reported.

Incorporating photocatalytic nanoparticles with biochar templates can produce biochar-supported photocatalysts (BSPs) and combine the advantages of biochar with catalytic nanoparticles.  相似文献   
17.
Recently, nanosized metal-oxides have been extensively investigated for their ability to remove metal ions from aqueous media. However, the activity and capacity of these nanosized metal-oxides for removing metal ions decrease owing to their agglomeration in aqueous media. Herein, we synthesized a highly stable and magnetically separable rosin-biochar-coated (RBC) TiO2@C nanocomposite through a facile and environment-friendly wet chemical coating process, followed by a one-step heating route (pyrolysis) for efficient removal of Cr(vi) from aqueous solution. An array of techniques, namely, TEM, HRTEM, TEM-EDS, XRD, FTIR, VSM, BET and TGA, were used to characterize the prepared nanocomposite. The pyrolysis of rosin into biochar and the fabrication of Fe onto the RBC-TiO2@C nanocomposite were confirmed by FTIR and XRD examination, respectively. Moreover, TEM and HRTEM images and elemental mapping using TEM-EDS showed good dispersion of iron and carbon on the surface of the RBC-TiO2@C nanocomposite. Sorption of Cr(vi) ions on the surface of the RBC-TiO2@C nanocomposite was very fast and efficient, having a removal efficiency of ∼95% within the 1st minute of reaction. Furthermore, thermodynamic analysis showed negative values of Gibb''s free energy at all five temperatures, indicating that the adsorption of Cr(vi) ions on the RBC-TiO2@C nanocomposite was favorable and spontaneous. Conclusively, our results indicate that the RBC-TiO2@C nanocomposite can be used for efficient removal of Cr(vi) from aqueous media due to its novel synthesis and extraordinary adsorption efficacy during a short time period.

A biochar-coated RBC-TiO2@C nanocomposite was synthesized using a wet chemical coating followed by a one-step heating route (pyrolysis) for the efficient removal of Cr(vi).  相似文献   
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Background The study was performed with an aim to map the pattern of metastasis of squamous cell carcinomas of buccal mucosa to various cervical lymph node levels and analyze its correlation with primary tumor size and histo-pathological grading. Material and Methods 254 patients with squamous cell carcinoma of the buccal mucosa treated with surgery first approach were analyzed retrospectively. The tumor size was noted from pre-operative CT Scans and were divided into early and advanced tumors. The resected specimen was studied to note the histo-pathological grading of the squamous cell carcinoma and the metastatic deposits at various lymph node levels. Results Out of 254 patients (149 females, 105 males), 145 patients showed histo-pathologically proven metastatic deposits in one or more lymph nodes out of which there were 56 patients showing occult metastasis. 78/145 patients showed metastatic involvement of level IB and/or IA lymph nodes, 31 showed involvement of level II and/or I lymph nodes, 27 showed involvement of level III with or without involvement of level I and II and 9 showed metastasis to level IV and V lymph nodes with or without level I, II or III lymph nodes. Cervical lymph node metastasis had statistically significant association with tumor size with advanced tumors showing worse pattern of metastatic spread beyond level I and II lymph nodes. As the degree of differentiation of squamous cell carcinoma reduced, they were more prone for cervical metastasis with moderately and poorly differentiated squamous cell carcinoma showing higher involvement of level III, IV and V lymph nodes. Conclusions The majority of buccal mucosa cases showed metastasis to level I, II and III lymph nodes out of which level IB and/or IA was most frequently involved. Metastasis to level IV and V lymph nodes was rare and was seen especially in patients with advanced primary tumor and poor histo-pathologic differentiation. Key words:Oral squamous cell carcinoma (OSCC), cervical lymph node metastasis, histologic differentiation, locally advanced disease.  相似文献   
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